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Capturing CO 2 and subsequently converting into valuable chemicals has attracted extensive attention. Herein, a series of biomass-based N-rich porous carbon materials with high specific surface area and pore volume were prepared using biomass waste soybean dregs as precursors. The nitrogen content was up to 4 % with different forms in the carbon skeleton such as pyridine-N, pyrrole-N. The synergistic effect of ultra-micropore (pore size <0.7 nm) and N-containing groups endowed the materials with a high CO 2 adsorption capacity, reaching 6.3 and 3.6 mmol g -1 at 0 and 25 °C under atmospheric pressure, respectively. In addition, the sufficient interaction between N-containing groups and CO 2 was demonstrated by solid-state nuclear magnetic resonance spectroscopy, and the captured CO 2 was possibly activated in the form of carbamate, which is conducive to subsequent conversion. Therefore, the supported catalyst with the as-synthetic porous carbon material as the carrier and Zn II as catalytic sites was prepared and successfully applied for carboxylative cyclization of propargylic amine with CO 2 to afford the 3-benzyl-5-methyleneoxazolidin-2-one. The results showed that CO 2 capture and in-situ conversion work effectively to produce highly value-added chemicals. In this process, the captured CO 2 could be activated and fixed into chemicals in mild conditions. More importantly, the energy consumption in CO 2 desorption and adsorbent regeneration could be avoided. The valorization of both solid waste and CO 2 to valuable chemicals provides an elegant strategy of killing three birds with one stone., (© 2022 Wiley-VCH GmbH.)

Photocatalytic synthesis has emerged as an efficient route to transform CO 2 into functionalized organic carbamates by photocatalysis. Herein, a catalyst-free carbamoyloxylation of arylacetones with CO 2 and amines under visible light was developed for the synthesis of O -β-oxoalkyl carbamates in yields up to 93%. This protocol proceeded smoothly with the assistance of inexpensive carbon tetrabromide at room temperature under atmospheric CO 2 pressure, leading to simultaneous construction of C-O and C-N bonds. Mechanism studies suggested the photoinduced hydrogen atom transfer (HAT) pathway followed by radical addition or single electron transfer (SET).

Objective: To establish the chromatographic fingerprint of supercritical carbon dioxide extract of Tripterygium wilfordii., Method: HPLC method was applied for quality assessment of T. Wilfordii, HPLC analysis was performed on Kromasil C18 (4. 6 mm x 250 mm, 5 microm) with the mixture of acetonitrile-1% per thousand H3PO4, as mobile phase in gradient mode. The samples were detected at UV of 267 nm with column temperature of 35 degrees C, analytic time was 80 min; Flow-rate was 1.0 mL x min(-1). The chromatographic fingerprint of ten batches of samples was determined, for establishing the chromatographic fingerprint of T. Wilfordii., Result: Indicating 27 peaks in common, identified 21 peaks with chemical reference and HPLC-MS, and the HPLC fingerprint was established., Conclusion: The method is steady and accurate with a good repeatability and can be used as a quality control method for T. Wilfordii.

A Cu/Co tandem catalysis protocol was developed to conduct the hydroformylation of olefins using CO2/H2 and PMHS (polymethylhydrosiloxane) as a readily available and environmentally friendly hydride source. This methodology was performed via a two‐step approach consisting of the copper‐catalyzed reduction of CO2 by hydrosilane and subsequent cobalt‐promoted hydroformylation with H2 and the in situ formed CO. The optimized triphos oxide ligand, which presumably facilitates the migratory insertion of CO gives moderate to excellent yields for both terminal and internal alkenes. This earth‐abundant metal catalysis provides a reliable and efficient way to afford useful aldehydes in industry using silicon by‐product PMHS as hydrogen source and renewable CO2 as carbonyl source. [ABSTRACT FROM AUTHOR]

In this work, the novel solid base Li/NaY was prepared via the solid state reaction between NaY zeolite and Li2CO3 at high temperature. When applied to the dimethyl carbonate (DMC) preparation through transesterification of ethylene carbonate (EC) and methanol, up to 89% yield of DMC with 99% selectivity can be accessed. The characterization results reveal the as‐synthesized Li/NaY possesses higher basicity than NaY. Furthermore, the Lewis acidity of the Li/NaY material is also enhanced due to the incorporation of lithium. Therefore, the Li/NaY can act as a dual functional catalyst in the transesterification reaction, thus leading to high efficiency. Notably, this catalyst can be easily recovered and reused for at least six times without obvious activity loss. This work provides a green synthetic route to DMC production and also sheds light on the development of solid basic catalysts. [ABSTRACT FROM AUTHOR]

To address the CO 2 accumulation in atmosphere, various initiatives have been proposed, among which CO 2 capture and utilization (CCU) is regarded as an appealing strategy to reconcile carbon emission and resource utilization. Especially, integrated CO 2 capture and utilization (ICCU), i.e. performing CO 2 capture and in-situ conversion can circumvent the energy-intensive CO 2 desorption step and thus facilitate establishing step- and energy-efficient process, rendering the conversion at mild conditions particularly at low pressure due to substantial activation upon CO 2 uptake. However, CO 2 capture and in-situ conversion is not the simple add-up of these two processes. Its successful implementation relies on the harmonization of CO 2 capture reagents, substrates and the corresponding catalysts. By far, tremendous efforts have been made in this field and a plethora of CO 2 capture reagents including inorganic bases, organic bases, ionic liquids and carbonaceous materials have been utilized to capture CO 2 and the conversion protocols such as hydrogenation, cycloaddition, carboxylative cyclization etc. have been explored for these captured CO 2. As a result, the valuable products containing methanol, methane, carbonates, carbamates, oxazolidinones, ureas, and quinazolinone have been obtained from CO 2 and more importantly, the CO 2 chemistry theory is also enriched via investigating the structure and reactivity of the captured CO 2 in various reactions. In this review, we summarize the progress on CO 2 capture and in-situ conversion based on the reaction types and corresponding CO 2 absorbents. It's hoped that this review can shed light on the design of CO 2 capture and in-situ conversion and inspire the further development of this field. • CO 2 capture and in-situ conversion is an important strategy for CO 2 utilization. • Its implementation relays on the convergence of sorbents and catalyst. • Organic and inorganic base, ionic liquids are efficient sorbents in this strategy. • Both reductive and nonreductive CO 2 conversion have been realized. [ABSTRACT FROM AUTHOR]

Abstract: In the last few years, photochemical and electrochemical CO2 transformations have attracted increasing attention in response to topical interest in renewable energy and green chemistry. The present minireview offers an overview about the current approaches for the photochemical and electrochemical carbon dioxide fixation with organic compounds. Valuable products, including carboxylic acids and heterocyclic compounds, are accessible through carboxylation and carboxylative cyclization, respectively. In photochemical and electrochemical processes, photo‐ or electro‐induced radical ions or other high‐energy organic compounds are considered as key intermediates to react with CO2. Besides, activation of CO2 to produce radical anion has also been reported. [ABSTRACT FROM AUTHOR]

Inside Back Cover picture shows The carps trying hard to make a successful jump over the Dragon Gate will change into fish‐dragons, which is a legend handed down in China over generations. The back cover picture shows photochemical and electrochemical CO2 transformations with organic compounds through the utilization of solar energy or electric energy, producing a series of valuable products, including carboxylic acids and hetero‐cyclic compounds. The combined utilization of both clean energy and CO2 has attracted increasing attention in sustainable development of renewable energy and green chemistry. Recent advances are summarized by He et al. on page 644–659. [ABSTRACT FROM AUTHOR]

[Display omitted] • Benzene ring incorporated g-C 3 N 4 microtubes are fabricated. • This material has improved light harvesting and carrier separation efficiency. • It can be applied in photocatalytic CO 2 reduction with Co(bpy) 3 Cl 2 as co-catalyst. • The catalytic system presents high efficiency and selectivity to CO. • Stability is the most attractive feature for this material. As a promising material for photocatalytic CO 2 reduction, graphitic carbon nitride (CN) and its modification has attracted significant attention. In this work, the in-plane benzene incorporated g-C 3 N 4 microtubes were fabricated via a hydrothermal self-assembly and subsequent thermal polymerization. It is revealed that introducing the π electron-rich benzene ring into the planar structure of g-C 3 N 4 can improve the availability of π electron and create the local asymmetry of heptazine structure. As a result, the separation and transportation of photogenerated charges are improved. Furthermore, the modified g-C 3 N 4 possesses relatively narrow band gap and enhances light absorption. When the in-plane benzene modified g-C 3 N 4 microtubes were applied to photocatalytic CO 2 reduction with Co(bpy) 3 Cl 2 as co-catalyst, a CO yield up to 322.66 μmol·g−1·h−1 was obtained, which was two times in comparison with the pristine g-C 3 N 4. This work confirms the effectiveness of in-plane benzene modification and 1D hollow structure formation in improving the photoelectric performance of g-C 3 N 4. Besides, it provides an efficient photocatalytic CO 2 reduction protocol with nonmetallic semiconductor material and earth-abundant metal co-catalyst. [ABSTRACT FROM AUTHOR]